import java.util.HashSet;
import java.util.Random;

public class Task05_05 {
    public static void main(String[] args) {
        {
            int arr[] = new int[10];
            Random rand = new Random();
            HashSet<Integer> set = new HashSet();

            while (set.size() <= 10) {
                set.add(rand.nextInt(20) + 1);

            }
            System.out.println(set);
        }
    }
}
